Displaying 20 results from an estimated 6000 matches similar to: "NLME / LMER: Multiple Membership Models"
2007 Jun 10
1
{nlme} Multilevel estimation heteroscedasticity
Dear All,
I'm trying to model heteroscedasticity using a multilevel model. To
do so, I make use of the nlme package and the weigths-parameter.
Let's say that I hypothesize that the exam score of students
(normexam) is influenced by their score on a standardized LR test
(standLRT). Students are of course nested in "schools". These
variables are contained in the
2007 Jul 30
1
Extract random part of summary nlme
Dear helpers,
I'm estimating multilevel regression models, using the lme-function
from the nlme-package. Let's say that I estimated a model and stored
it inside the object named 'model'. The summary of that model is
shown below:
Using summary(model)$tTable , I receive the following output:
> summary(model)$tTable
Value Std.Error DF t-value
2007 Jul 31
1
Extracting random parameters from summary lme and lmer
LS,
I'm estimating multilevel regression models, using the lme-function
from the nlme-package. Let's say that I estimated a model and stored
it inside the object named 'model'. The summary of that model is
shown below:
Using summary(model)$tTable , I receive the following output:
> summary(model)$tTable
Value Std.Error DF t-value
2007 Apr 16
1
Modelling Heteroscedastic Multilevel Models
Dear ListeRs,
I am trying to fit a heteroscedastic multilevel model using lmer{lme4-
package). Take, for instance, the (fictive) model below.
lmer(test.result ~ homework + Sex -1 + (1 | School))
Suppose that I suspect the error terms in the predicted values to
differ between men and women (so, on the first level). In order to
model this, I want the 'Sex'-variable to be random on
2007 Apr 06
2
plotting multilevel / lme lines
Dear expeRts,
I am trying to plot a lme-object {package nlme) in such a way, that
on a selected level the x-axis represents the value on a selected
predictor and the y-axis represents the predicted-outcome variable.
The graphs would than consist of several lines that each represent
one group. I can't find such a plotting function.
I could write such a function myself, based on
2007 Jul 30
0
Extracting random parameters from summary lme
LS,
I'm estimating multilevel regression models, using the lme-function
from the nlme-package. Let's say that I estimated a model and stored
it inside the object named 'model'. The summary of that model is
shown below:
Using summary(model)$tTable , I receive the following output:
> summary(model)$tTable
Value Std.Error DF t-value
2008 Aug 05
2
Adding .PDF files to a package
Deal all,
new as I am to developing packages for R-Project, I apologize on
beforehand for questions that are too obvious. I am trying to 'add' a
PDF document containing some detailed information to a package.
The way I understand the Rexts.pdf document, I should add my .PDF
document to the /inst/doc/ folder, and links to the files should be
build automatically. However, after
2006 Aug 26
2
Importing data from clipboard on Mac OSX
Dear R users,
I am trying to get data from the clipboard into R on MacOSX. I tried
the following, but got an error message:
read.delim("clipboard")
Error in file(file, "r") : unable to open connection
In addition: Warning message:
unable to contact X11 display
Obviously, I'm not running R using X11. I'm wondering, can I import
data from the clipboard on MacosX?
2007 Dec 07
2
Same regression per sub-group: apply?
Dear helpers,
I've come up with what is probably a simple problem, but I cannot
find the solution. I have a data-set containing survey-data from
several countries. What I want to do is to perform some regression
analyses, for each country separately. The question is, how to do
this nicely (thus without repeating the same syntax with another
`subset' argument).
I thought of the
2006 May 19
1
Weird LM behaviour
Dear R users,
experimenting with the lm function in R, I've encountered some
behaviour I don't understand with my limited knowledge of regression.
I made a data-'set' of three measurements (see syntax below). Using
lm (linear model) to fit the regression-line, I expected to find an
intercept of 2.0 and a slope of 0, but in fact the slope is slightly
below zero. Amazed by
2006 Sep 26
2
Statistical data and Map-package
Dear helpeRs,
I'm working with the map-package and came upon a problem which I
couldn't solve. I hope onee of you can. If not, this can be seen as a
suggestion for new versions of the package.
I'm trying to create a map of some European countries, filled with
colors corresponding to some values. Let's say I have the following
countries and I assign the following colors
2005 Aug 18
1
Error messages using LMER
Dear All,
After playing with lmer for couple of days, I have to say that I am
amazed! I've been using quite some multilevel/mixed modeling packages,
lme4 is a strong candidate for the overall winner, especially for
multilevel generzlized linear models.
Now go back to my two-level poisson model with cross-classified model.
I've been testing various different model specificatios for the
2006 Aug 22
1
Total (un)standardized effects in SEM?
Hi there,
as a student sociology, I'm starting to learn about SEM. The course I
follow is based on LISREL, but I want to use the SEM-package on R
parallel to it.
Using LISREL, I found it to be very usable to be able to see the
total direct and total indirect effects (standardized and
unstandardized) in the output. Can I create these effects using R? I
know how to calculate them
2006 Jan 08
1
lmer with nested/nonnested groupings?
I'm trying to figure out how to use lmer to fit models with factors that
have some nesting and some non-nested groupings. For example, in this
paper:
http://www.stat.columbia.edu/~gelman/research/published/parkgelmanbafumi.pdf
we have a logistic regression of survey respondents' political
preferences (1=Republican, 0=Democrat), regressing on sex, ethnicity,
state (51 states within 5
2013 May 14
1
Sampling Weights and lmer() update?
Perhaps I am not looking in the right place, but I am looking for a way to
use lmer() to run a multilevel model that incorporates sampling weights. I
have used the Lumley survey package to use sampling weights in the past,
but according to post I found online from Thomas Lumley in mid-2012, R is
currently not equipped to be able to do this.
His post is here:
2012 Nov 20
0
Multilevel analysis using nlme (lme) . Error using z-scores
Hi,
i am trying to learn something about multilevel analysis using a great
"Discovering statistics using R". I constructed some sample data and then
tried to fit a model. Generally model fits well, however when trying to fit
the same model using z-score (standarizded) variables i got an error:
Error in lme.formula(z_wyn ~ z_IQ + Kasa, data = la, random = ~z_IQ | :
nlminb problem,
2005 Aug 03
2
Multilevel logistic regression using lmer vs glmmPQL vs. gllamm in Stata
Dear all,
I am trying to replicate some multilevel models with binary outcomes
using R's "lmer" and "glmmPQL" and Stata's gllmm, respectively.
The data can be found at <http://www.uni-koeln.de/~ahf34/xerop.dta>.
The relevant Stata output can be found at <http://www.uni-
koeln.de/~ahf34/stataoutput.txt>. First, you will find the
unconditional model,
2006 Jan 03
3
Package for multiple membership model?
Hello all:
I am interested in computing what the multilevel modeling literature calls a multiple membership model. More specifically, I am working with a data set involving clients and providers. The clients are the lower-level units who are nested within providers (higher-level). However, this is not nesting in the usual sense, as clients can belong to multple providers, which I understand
2010 Jan 11
2
warning inside loop
Hi,
I'm running some data simulations using (mixed effects)* regression models
that show difficulty to converge. Therefore, I seek a way of capturing
warnings (of false convergence) inside a loop.
Inside that loop, I modify data and estimate a model. I do so many times
with slightly different modifications of the data. Next, I extract some of
the model parameters and store these in a matrix.
2017 Mar 09
0
(no subject)
Job Title: Sr Research Associate I
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The mission of the Institute for Child, Youth and Family Policy (ICYFP) is
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